phpstrlen

strlen() php function giving the wrong length of unicode characters

I am trying to get the length of this unicode characters string

$text = 'نام سلطان م';
$length = strlen($text);
echo $length;

output

20

How it determines the length of unicode characters string?

Solution

  • strlen() is not handling multibyte characters correctly, as it assumes 1 char equals 1 byte, which is simply invalid for unicode. This behavior is clearly documented:

    strlen() returns the number of bytes rather than the number of characters in a string.

    The solution is to use mb_strlen() function instead (mb stands for multi byte) (see mb_strlen() docs).